An additive basis for the cohomology rings of regular nilpotent Hessenberg varieties

In this paper we construct an additive basis for the cohomology ring of a regular nilpotent Hessenberg variety which is obtained by extending all Poincare duals of smaller regular nilpotent Hessenberg varieties. In particular, all of the Poincare duals of smaller regular nilpotent Hessenberg varieties in the given regular nilpotent Hessenberg variety are linearly independent.Comment: 41 pages, 7 figure

Supramolecular sulfur-containing polymers with hydrogen bonding

Although sulfur-containing polymers have been realized by various methods such as copolymerization and reverse vulcanization, there are few reports on the synthesis of supramolecular sulfur-containing polymers in which a supramolecular polymer is fused with a sulfur-containing polymer. Herein, we prepare a supramolecular sulfur-containig polymer by introducing a 2-ureido-4[1H]pyrimidinone (UPy) unit at both ends of linear sulfur and connecting between the UPys via hydrogen bonding.This is an Accepted Manuscript of an article published by Taylor & Francis in Journal of Sulfur Chemistry on 03 Mar 2023, available at 10.1080/17415993.2023.2183773

Osteogenic response of mesenchymal progenitor cells to natural polysaccharide nanogel and atelocollagen scaffolds: A spectroscopic study

A natural polysaccharide scaffold, referred to as "freeze-dry nanogel-crosslinked-porous" (FD-NanoCliP) gel, was tested in comparison with an atelocollagen scaffold with respect to osteogenesis versus the mouse mesenchymal progenitor cell line KUSA-A1. The amphiphilic polysaccharide network, engineered in its structure to fit chemically crosslinked nanogels as building blocks into a physically crosslinked porous gel, revealed a superior osteointegrative performance as compared to the soluble atelocollagen network and a peculiar c-plane orientation growth of apatite crystallites, which resembled the structure of natural enamel. Besides evaluating osteogenesis in the FD-NanoCliP gel scaffold, an additional purpose of this study was to assess its chemical composition at the nanoscale and, through its knowledge, to interpret the osteogenic response of mesenchymal cells. In addition to conventional (optical and electron) microscopy and biological evaluation kits, the peculiar chemistry of the FD-NanoCliP gel scaffold and the formation of apatite on it were characterized by means of several independent analytical probes at the molecular scale, which included Raman, cathodoluminescence, energy dispersive X-ray, and X-ray fluorescence spectroscopies. This body of information consistently provided evidence for a peculiar chemistry developed in osteogenesis at the polysaccharide scaffold surface. Such chemistry is not available in soluble atelocollagen and it is key in the superior bioactivity found in the polysaccharide network

The Influence of Environmental Exposure to Formaldehyde in Nasal Mucosa of Medical Students during Cadaver Dissection

ABSTRACTBackgroundEnvironmental exposure to formaldehyde is commonly associated with clinical symptoms such as mucosal irritation and olfactory disorders. However, the impact of such exposure on the development of mucosal inflammation and its outcome has not been carefully evaluated.MethodsThe observational non-comparative study was planned. The study population consisted of group of 41 medical students who had signed up for a cadaver dissection course as part of their gross anatomy teaching at the school of medicine Chiba University in Japan. During such dissection course, the students are exposed to variable levels of environmental formaldehyde routinely employed for the preservation the cadavers. The subjects were evaluated by a detailed medical examination. We measured their serum IgE levels. In addition, an olfaction test and nasal mucosal sensitivity to histamine was serially determined, immediately before and after the course and 6 months after the completion of the course.ResultsOlfactory abnormalities were observed in 13/41 (32%) subjects and increased nasal mucosal hypersensitivity to histamine was observed in 17/41 (41%) during and immediately after completion of the course. These subjects had evidence of preexisting allergic rhinitis. 6/41 (15%) other students with no prior evidence of allergic rhinitis also exhibited formaldehyde associated clinical symptoms during the dissecting course. However, the symptoms disappeared upon completion of the course in all subjects studied.ConclusionsTemporary abnormalities in the olfaction test and increased nasal mucosal hypersensitivity to histamine were observed in a few students with preexisting allergic rhinitis after environmental exposure of high concentrations of formaldehyde. These effects appeared to be transient